I have a 2000 Silverado Z-71 with 75,000 miles. When starting from a dead stop my accelerator requires a good hard push to start moving. Once free, the push usually causes me to spin burn a little rubber while getting under way. The problem is interrmitant and I heard on car talk that my throttle box may have excessive carbon build-up and require cleaning. However a coworker had the same problem and had to replace the throttle box. Any ideas?

You do not have to replace the box. THe throttle body just needs to be cleaned. It is a well known fact that the dealers use that to make you buy a new one. Just clean yours and you might have to make an adjustment on your throttle body. Either one of these will fix your problem.